Conventional digital broadcasting stations of this type do not transmit information indicating other broadcasting stations that are broadcasting programs with the same content as the digital broadcasting station. Moreover, even if a digital broadcasting station transmitted that type of information, the information has not been used by receivers installed in vehicles. When the reception of a program being viewed/listened to on a vehicle-mounted receiver became impossible because the received signal level had become too low or for some other reason, accordingly, the viewer/listener had to select receivable broadcasting stations one by one manually and determine whether they were broadcasting the same program content.
A known method of avoiding this troublesome procedure is, for example, for the digital broadcasting station to broadcast program information including information about affiliated stations; when the vehicle-mounted receiver decides that program reception is impossible because the receiving level is too low, for example, it automatically searches for another receivable broadcasting station; if it finds another receivable broadcasting station, it extracts that broadcasting station's affiliated station information from that broadcasting station's program information; if the affiliated station information indicates that the station is affiliated with the station that was broadcasting the program being viewed/listened to before the receiving level dropped, the receiver automatically selects that broadcasting station (see, for example, Patent Document 1, claim 1 and FIG. 1).
Another known method automatically conducts a channel search when it decides that program reception is impossible because the receiving level is too low, extracts from the program information of each channel found the title of the program that the broadcasting station is broadcasting, and compares that program title with the program title of the program that was being viewed/listened to before the receiving level dropped; if they are the same (or if they are in the same genre, or if their program identification numbers are the same when compared), the receiver selects the broadcasting station (see, for example, Patent Document 1 claims 2-5 and FIG. 1).    Patent Document 1: Japanese Patent Application Publication No. 2004-140690 (claims 1-5 and FIG. 1).